Method and system for removing oxygen and carbon dioxide during red cell blood processing using an inert carrier gas and manifold assembly

ABSTRACT

A portable assembly for processing red blood cells RBCs including a disposable blood collection set including a blood bag, an anaerobic storage bag and an oxygen and/or oxygen and carbon dioxide depletion device disposed between the blood collection bag and anaerobic storage bag. The portable assembly further provides for a gas circulation device in fluid communication with the oxygen or oxygen and carbon dioxide depletion device, The gas circulation device includes a pressure source that is able circulate flushing gas through the depletion device as RBCs pass from the blood collection bag, through the depletion device and into the anaerobic storage bag.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.13/432,810 filed on Mar. 28, 2012 (pending), which claims benefit ofU.S. Provisional Application Ser. No. 61/468,377 filed on Mar. 28, 2011(expired), the contents of which are incorporated by reference herein intheir entireties.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present disclosure relates to a portable blood treatment manifoldassembly. More, particularly, the present disclosure relates to aportable blood treatment manifold assembly for leukoreduction and oxygenand/or carbon dioxide depletion of blood in preparation for bloodstorage and/or transfusion to a recipient.

2. Background of the Art

The supplies of liquid blood in are currently limited by storage systemsused in conventional blood storage practice. Using current systems,stored blood expires after about 42 days of refrigerated storage at atemperature above freezing (i.e.1-6° C.) as packed blood cellpreparations. Red blood cells (RBCs) may be concentrated from wholeblood with separation of the liquid blood component (plasma). Expiredblood cannot be used and is discarded.

There are periodic shortages of blood that occur due to donationfluctuation, emergencies and other factors. The logistics of bloodsupply and distribution impact the military, especially during times ofcombat and remote hospitals or medical facilities making bloodprocessing or transfusions very difficult. Accordingly, there is a needto be able to rapidly prepare RBCs for storage or for transfusions inremote locations.

Storage of frozen blood is known in the art but such frozen blood haslimitations. For a number of years, frozen blood has been used by bloodbanks and the military for certain high-demand and rare types of blood.However, frozen blood is difficult to handle. It must be thawed whichmakes it impractical for emergency situations. Once blood is thawed, itmust be used within 24 hours. U.S. Pat. No. 6,413,713 to Serebrennikovis directed to a method of storing blood at temperatures below 0° C.

U.S. Pat. No. 4,769,318 to Hamasaki et al. and U.S. Pat. No. 4,880,786to Sasakawa et al. are directed to additive solutions for bloodpreservation and activation. U.S. Pat. No. 5,624,794 to Bitensky et al.,U.S. Pat. No. 6,162,396 to Bitensky et al., and U.S. Pat. No. 5,476,764are directed to the storage of red blood cells under oxygen-depletedconditions. U.S. Pat. No. 5,789,151 to Bitensky et al is directed toblood storage additive solutions.

Additive solutions for blood preservation and activation are known inthe art. For example, Rejuvesol (available from enCyte Corp., Braintree,Mass.) is add to blood after cold storage (i.e., 4° C.) just prior totransfusion or prior to freezing (i.e., at −80° C. with glycerol) forextended storage. U.S. Pat. No. 6,447,987 to Hess et al. is directed toadditive solutions for the refrigerated storage of human red bloodcells.

In light of current technology, there is a need for a portable and costeffective apparatus and methodology for the preparation of RBCs thatremoves leukocytes and oxygen and/or carbon dioxide in advance oftransfusion or in preparation for anaerobic storage.

SUMMARY OF THE INVENTION

Accordingly, the present disclosure provides a system that is capable ofremoving oxygen and/or carbon dioxide and/or leukocytes from RBCs inadvance of transfusion or for further storage in an anaerobicenvironment.

The present disclosure also provides for a system and methodology forthe preparation of RBCs in advance of transfusion or for further storagein an anaerobic environment.

It is a further object of the present disclosure to provide astand-alone portable system that has an oxygen or an oxygen/carbondioxide depletion (OCDD) device that removes oxygen or oxygen and orcarbon dioxide from RBCs passing through the device. The OCDD deviceoperates with a gas exchange system that pumps gas into the devicethrough which RBCs that first passes through an oxygen or oxygen/carbondioxide (OCDD) device to remove oxygen or oxygen/carbon dioxide fromsuch RBCs. The RBCs are thereby depleted of oxygen or oxygen/carbondioxide and deposited in a blood storage bag for extended storage orstorage in advance of transfusion.

It is a still further object of the present disclosure to provide astand alone portable system that pumps gas into the device through whichRBCs pas through a leukoreduction filter and an oxygen and/or carbondioxide (OCDD) device to remove leukocytes and oxygen or oxygen/carbondioxide from such RBCs, respectively. The RBCs are thereby free ofleukocytes and depleted of oxygen or oxygen/carbon dioxide and depositedin a blood storage bag for extended storage or storage in advance oftransfusion.

It is still a further object of the present disclosure to provide astandalone portable system that circulates oxygen depleted and or/carbondioxide adjusted air air or inert gas mixtures through an OCDD device toremove such gases from RBCs flowing through the filter in preparationfor anaerobic storage or transfusion. Such system contains oxygen,carbon dioxide and/or partial pressure sensors between an inlet manifoldthat receives oxygen and/or carbon dioxide rich air or inert gas from anOCDD device and an outlet manifold. The sensors monitor and regulateoxygen and or carbon dioxide levels in air or inert gas mixturesreceived in the outlet manifold and monitor oxygen and carbon dioxidepartial pressure of filtered gas that is pumped pumped back to OCDDdevice.

It is still a further object of the present disclosure to provide astandalone portable system that reduces leukocytes and circulates oxygenand/or carbon dioxide adjusted air or inert gas mixtures through an OCDDdevice to remove such gases from RBCs in preparation for anaerobicstorage or transfusion. Such system contains oxygen, carbon dioxideand/or partial pressure sensors between an inlet manifold that receivesoxygen and/or carbon dioxide rich air or inert gas mixtures from an OCDDdevice and an outlet manifold that feeds oxygen and carbon dioxidedepleted air or inert gas mixtures back is to the OCDD device. Thesensors monitor and regulate oxygen and or carbon dioxide levels in gasreceived in the outlet manifold and monitor oxygen and carbon dioxidepartial pressure of gas that is pumped back to OCDD device.

A portable assembly for processing red blood cells RBCs including adisposable blood collection set including a blood bag, an anaerobicstorage bag and an oxygen and/or oxygen and carbon dioxide depletiondevice disposed between the blood collection bag and anaerobic storagebag. The portable assembly further provides for a gas circulation devicein fluid communication with the oxygen or oxygen and carbon dioxidedepletion device, The gas circulation device includes a pressure sourcethat is able circulate flushing gas through the depletion device as RBCspass from the blood collection bag, through the depletion device andinto the anaerobic storage bag.

A portable assembly for processing red blood cells (RBCs) including anoxygen or oxygen and carbon dioxide depletion (OCDD) device. The OCDDdevice includes a cartridge having an inlet and an outlet and aplurality of hollow fibers disposed between the inlet and the outlet fortransporting RBCs through the OCDD device. The plurality of hollowfibers are surrounded by a continuous space. The portable assemblyincludes a gas exchange device in fluid communication with the OCDDdevice. The gas exchange device includes a pressure source that is ableto circulate a flushing gas through the continuous space and removeoxygen and/or carbon dioxide from RBCs passing through the OCDD device.

These and other objects and advantages of the present invention andequivalents thereof, are achieved by the methods and compositions of thepresent invention described herein and manifest in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1a illustrates a portable blood processing system according to thepresent disclosure;

FIG. 1b illustrates an alternative embodiment of the present disclosurein which red blood cells are processed using a load cell;

FIG. 1c illustrates the OCDD device of the embodiment of FIG. 1bdirectly connected to the processing system;

FIG. 1d illustrates a collection system that incorporates a flowregulator according to the embodiment of FIG. 1 b;

FIG. 1e illustrates a collection system that incorporates aleukoreduction filter with an OCDD device;

FIGS. 2a through 2c illustrate a leukoreduction filter incorporated intoan OCDD device according to the embodiment of FIG. 1 e;

FIG. 2d illustrates an OCDD device of the embodiment of FIG. 1 a;

FIG. 3 illustrates an OCDD device according to a further embodiment ofthe present disclosure having OCCD device, leukoreduction filter andplasma separation device in a unitary structure.

DETAILED DESCRIPTION OF THE DISCLOSURE

Referring to FIG. 1, a stand alone blood processing system is shown andreferenced using reference numeral 10. System 10 includes a housing 15and supports a blood collection and depletion system 100 (hereinafter“collection system 100”).

Collection system 100 includes a blood bag 200, a leukoreduction filter300, an oxygen and/or carbon dioxide depletion (OCDD) device 400 and ananaerobic storage bag 600. Device 400 is able to deplete oxygen oralternatively, oxygen and carbon dioxide from gas from RBCs. Collectionsystem 100 is suspended within system 10 to enable convenient movementand transport of blood preparation processes in locations that may beremote from a standard hospital or clinical setting. The orientation ofsystem 100, permits RBCs in blood bag 200 to flow under the force ofgravity to anaerobic storage bag 600. Although a single collectionsystem 100 is shown, stand 12 of housing 15 could carry as many as tenor more such systems for processing. Housing 15 includes a gascirculation device including a pressure source such as a pump 30 or avacuum or a pressurized container, a valve/pressure regulator 40 andfurther components that will be discussed further that enable gas tocirculate and pass through OCDD device 400. Inlet 410 and outlet 415(FIG. 2d ) that area connected to tubing 427 and 426, respectively.

Collection system 100 includes a blood bag 200 that contains RBCs thathave been collected from whole blood. Generally, whole blood iscollected from a donor using traditional methods and processed usingcentrifugation to separate plasma and RBCs. Blood bag 200 is a standardblood collection bag. RBCs are collected in a blood bag 200 that maycontain an additive. An additive solution, such as, for example, OFAS3,includes adenine, dextrose, mannitol, NaH₂PO₄, and optionally NaCland/or NH₄Cl. Additive solution OFAS3 preferably comprises ingredientshaving the following ranges: about 0.5-4.0 mmole/liter of adenine, about50-150 mmole/liter of dextrose, about 20-70 mmole/liter of mannitol,about 0-100 mmole/liter of NaCl, about 2-20 mmole/liter of NaH₂PO₄, andabout 0-30 mmole/liter NH₄Cl. Preferably, OFAS3, has an adjusted pH fromabout 5.5-7.5 and includes about 2 mmole/liter adenine, about 110mmole/liter dextrose, about 55 mmole/liter NaCl, and about 12mmole/liter NaH₂PO₄ and an adjusted pH of about 6.5. Additives such asSAGM, PAGG-SM, AS-1, AS-3, AS-5, SOLX, MAPS, PAGG-GM or any additiveapproved for blood storage may also be used in this system.

RBCs contained in blood bag 200 flow under the force of gravity toleukoreduction filter 300 and through OCDD device 400. Leukoreduction isthe process of removing white blood cells from the whole blood or RBCs.Leukocytes in blood products can cause immunosuppressive effects and canpre-dispose patients to an increased risk of viruses, fevers, and havedeleterious effects on RBCs.

Leukoreduction reduces RBC storage lesions, reduces primaryalloimunization and reduces total number of transfusion reactions.

The process of leukoreducing RBCs preferably occurs after the RBCs havebeen separated from the plasma and can occur before or after removal ofoxygen and carbon dioxide have been removed from the RBCs. In eithercase, leukoreduction should occur before storage of RBCs and anaerobicstorage bag 600.

Referring to FIGS. 2a, 2b, and 2c leukoreduction filter 300 isincorporated into OCDD device 500. OCDD device 500 includes a cartridge505, an inlet 510, a leukoreduction filter 520, a plurality of hollowfibers 530, and a fiber support 540 to hold the plurality of hollowfibers 530. OCDD device 500 also includes an outlet 515 for passage ofRBCs. Leukoreduction filter 520 is preferably a fibrous or a felt-likefiltering material that captures leukocytes, prior to such leukocytestravelling through plurality of hollow fibers 530. Fiber support 540supports the plurality of hollow fibers 530 in a vertical configurationand may be made from a material such as polyurethane or a similarmaterial. Either whole blood or pRBC flow through filter 520 duringleukoreduction process. OCDD device 500 is in communication with gasfrom pump 30 via an inlet 524 and an outlet 528.

OCDD cartridge 500 contains approximately 5000 fibers for the passage of

RBCs. More or fewer fibers may be used to generate a sufficient surfacearea for gas exchange to reduce the oxygen and/or carbon dioxideconcentrations to the desired levels. Plurality of hollow fibers 530 arefor the purpose of removing oxygen or oxygen and carbon dioxide from RBCand will be discussed further below. Gas spaces 550, outside of hollowfibers and inside of cartridge 505, that surround plurality of hollowfibers 530 and are filled with a carrier gas. Gas permeable material orporous materials of plurality of hollow fibers 530 enable oxygen andcarbon dioxide to pass from RBCs to carrier gas when such gas iscirculated through OCDD device 500. OCDD device 500 depletes, O₂ andCO₂, or O₂, or CO₂ alone, or O₂ with specific levels of CO₂ by supplyingan appropriate composition of flushing gas. Gases appropriate fordepletion for use in OCDD devices are any inert gasses that will notcause harm to the RBCs or blood recipient, for example, Ar, He, N₂,Ar/CO₂, He/CO₂ or N₂/CO₂.

RBCs flow into OCDD device 500 to be depleted of oxygen or oxygen andcarbon dioxide. OCDD device 500 reduces the degree of RBC hemoglobinoxygen saturation levels to less than 3% and the carbon dioxide partialpressure to less than 50 Torr at 37° C. OCDD device 500 is a combinationoxygen and carbon dioxide filter that removes oxygen and carbon dioxidefrom RBCs to enhance the storage life of such RBCs and promotes optimaltransfusion. OCDD device 500 is used with housing 115 and stand 12 ofFIG. 1e and contains same components as embodiment of FIG. 1 a.

Alternatively, as shown in FIG. 2d , an OCDD device 400 does not containthe leukoreduction capability and is only capable of depleting oxygen oroxygen and carbon dioxide from RBCs passing there through. FIG. 2dillustrates an OCDD device 400 that has an inlet 410 for the entry ofRBCs, an outlet 415 for the passage of RBCs, and a plurality of fibers430 through which such RBCs pass to be deleted of oxygen and/or carbondioxide gas. OCDD device 400 also contains an entry port 424 forflushing gas and an exit port 428 for the egress of flushing gas and aplurality of spaces 450 that surround plurality of fibers 430 that areinside of cartridge 405 and where gas exchange from RBCs to flushing gasoccurs. The circulation of gas through OCDD device 400 via entry port424, exit port 428 and plurality of spaces 450 ensures that the partialpressure of oxygen and carbon dioxide in RBCs stored in bags 600 is atacceptable levels for optimal storage of RBCs.

Referring to FIG. 1a , again, housing 15 includes an inlet manifold 20,a pump 30, an outlet manifold 60 and an inlet valve/pressure regulator40. OCDD cartridge 400 is connected to inlet manifold 20 and outletmanifold 60 by tubing 27 and 13 or direct connections 128 and 124 (FIG.1c ) respectively. A first oxygen/carbon dioxide sensor 50 and a secondoxygen/carbon dioxide sensor 90 are disposed between inlet manifold 20and outlet manifold 60. System 10 is connectable to an AC outlet orother supply of power for operation of pump 30. Alternatively, system 10can connect to a battery for remote operation of system 10.

Housing 15 contains a disposable or re-usable sorbent cartridge 75 thatis disposed between inlet manifold 20 and outlet manifold 60 to purifyand air or inert gas mixture that has passed through OCDD device 400.Sorbent cartridge 75 is a large cartridge that is preferably iron basedor other inorganic and/or organic compound that can physically orchemically absorb oxygen or oxygen/carbon dioxide. Sorbent cartridge 75contains an oxygen and/or a carbon dioxide sorbent 76. As an alternativeto a large sorbent pack or organic and inorganic compounds, oxygen andcarbon dioxide can also be depleted from oxygen and carbon dioxide richair or inert gas mixture by using membrane filters designed for gasseparation, such as those found in nitrogen generator systems. Inaddition to oxygen or oxygen/carbon dioxide sorbent 76, sorbentcartridge 75 also includes activated charcoal filter 78 to absorbvolatiles produced by oxygen or oxygen/carbon dioxide sorbent. Charcoalfilter 78 also includes a HEPA filter to remove any particulates.

System 10 also includes various sterilization filter sensor assemblies70, 80 and 85. Sterilization filter sensor assembly 70 are disposebetween tubing 23 and inlet manifold 20. Sterilization filter sensorassembly 80 is disposed between outlet manifold 60 and tubing 27.Filters 70 and 80 capture any pathogens and/or particulates that couldenter gas flow between respective tubing and manifold and compromisefiltration and or purification of RBCs. Filters in 70 and 80 filtersensor assemblies monitor levels partial pressures of oxygen and carbondioxide for an individual OCDD 400 (or 500). Sterilization filter 85 isdisposed between external portion of housing 15 and inlet valve pressureregulator 40. Sterilization filter filter sensor assembly 85 monitorsgas entering pump 30. Filter in filter sensor assembly 85 capturepathogens and particulates between system 10 and ambient air or inertgas mixture and are also able to sense levels of oxygen, carbon dioxide,temperature and pressure and humidity. Filter sensor assemblies 70, 80and 85 also function as sensors and are in communication with controller35. Controller 35 is programmed with predetermined set points to monitorand control concentration and flow rate of oxygen and carbon dioxide,temperature, humidity and total pressure of the gas mixtures. Shouldlevels not be appropriate, a warning signal, such as a light or alarm,informs an operator that sorbent cartridge, sterilization filter or HEPAfilter should be replaced.

Housing 15 includes casters 25 to permit movement and positioning ofsystem 10. System 10 also includes a large sorbent cartridge 75 orhollow fiber gas separation module.

In operation, and as shown in FIG. 1, RBCs flow from collection bag 200into OCDD cartridge directly or via leukoreduction filter. Flushing gasis simultaneously circulated through OCDD cartridge 400. The flow ofoxygen or oxygen/carbon dioxide adjusted gas and oxygen/carbon dioxiderich gas to and from OCDD cartridge 400 is carried by tube 27 and tube23, respectively. Tube 23 is connected to inlet manifold 20 and tube 27is connected to outlet manifold 60. Tube 23 is connected to inletmanifold by a sterilization filter sensor assembly 70. Similarly, outletmanifold 60 is connected to tube 27 by sterilization filter 80.

After oxygen rich air or inert gas mixture egressing from OCDD device400 via tubing 23, such air or inert gas mixture is received at inletmanifold 20, and pumped via pump 30 through sensor 50. Pump 30 operatesto maintain gas flow through system 10. Pump 30 is preferably anelectrically driven pump that regulates pressures and flows. Pump 30 isconnected to a valve 40, preferably a one way valve and pressureregulator that accepts ambient air or inert gas mixture at ambientpressure or insert gasses at elevated pressures. Sensor 50 and sensor 90measure partial pressure of oxygen and carbon dioxide, in addition togas partial pressure, temperature, flowrate total pressure and humidityof the entire portable assembly. Air or inert gas is purified incartridge 75 and returned to OCDD 400 to continue to depletion RBCsbefore such RBCs flow into anaerobic storage bag 600.

FIGS. 1b through 1d show an alternative embodiment of a housing 115.Housing 115 contains similar gas exchange components as housing 15.Namely, housing 115 also contains an inlet manifold 20, a pump 30, anoutlet manifold 60 and an inlet valve/pressure regulator 40 containedwithin housing 115. Housing 115 also contains a load cell 6 that isconnected to bag 200 and a flow regulator valve 470. Load cell 6measures the unit weight in bag 200 and communicates change in mass inbag to a controller 35 that communicates with flow regulator valve 470to monitor flow of RBCs through OCDD device 400. By monitoring change ofmass of RBCs in bag 200, valve 470 can be adjusted to ensure that RBCsremain in OCDD device 400 for adequate oxygen or oxygen and carbondioxide removal. Controller 35 is in electrical communication with loadcell 6, flow regulator valve 470 and oxygen saturation sensor 475.Oxygen saturation sensor 475 measures oxygen saturation levels in RBCs.Controller 35 receives signals indicative of oxygen saturation levelsand in turn sends signal to adjust flow regulator valve 470 o assureadequate oxygen depletion levels in RBCs. The several bags 200 (FIG. 1b) can be connected to housing 115 and be similarly equipped with a flowregulator valve 470 although only one flow regulator 470 is shown.Housing 115 has an outside surface to which OCCD devices 400 can bedirectly connected via couplings. By configuring OCDD devices 400, asshown in FIGS. 1 b through 1 d, so that they are directly connected tohousing 115 via couplings 124 and 128, the need for tubing of theembodiment of FIG. 1a is eliminated. The configuration of housing 115can also be used with devices 500 that include leukoreductioncapability.

Referring to FIG. 3, a multifunction OCDD device 700 is a combinationleukoreduction filter 710, OCDD device 720, in combination with a plasmaseparator 730. Multifunction OCDD device 700 eliminates the need forseparation of the whole blood, received from donor, which is currently aseparated by using a centrifuge. By combining these three devices into asingle device, the need for a separate centrifuge, a highly costly andcumbersome device, is eliminated. This embodiment contains aleukreduction portion 710, a OCDD device 720 and a plasma separator 730.Plasma flows through port 740 to a further collection bag for furtherprocessing. Accordingly, in this embodiment, whole blood can becollected from a donor, leukocytes can be removed, oxygen, or oxygen andcarbon dioxide can be removed and plasma and platelets can be removed topass RBCs through device. The RBCs are then deposited into collectionbag 600 for storage or transfusion to a recipient. Multifunction OCDD700 as part of collection system 100 and system 10 permit rapidtransformation of whole blood to stored RBCs for immediate storage ortransfusion to a recipient.

Although the present disclosure describes in detail certain embodiments,it is understood that variations and modifications exist known to thoseskilled in the art that are within the disclosure. Accordingly, thepresent disclosure is intended to encompass all such alternatives,modifications and variations that are within the scope of the disclosureas set forth in the disclosure.

We claim:
 1. A method of processing red blood cells (RBCs) comprising:filtering a flushing gas source through a gas circulation device togenerate sterile flushing gas, said gas circulation device comprising,in fluid communication with each other: a flushing gas source providingsaid flushing gas; a gas outlet manifold; a first gas sterilizationfilter; a second gas sterilization filter; one or more gas sensorassemblies; a gas inlet manifold; and a controller, wherein said one ormore gas sensor assemblies are selected from the group consisting of anoxygen sensor, an oxygen partial pressure sensor, a carbon dioxidesensor, a carbon dioxide partial pressure sensor, and combinationsthereof; providing said sterile flushing gas to an oxygen or oxygen andcarbon dioxide depletion (OCDD) device; and flowing said RBCs throughsaid OCDD device to remove oxygen or oxygen and carbon dioxide from saidRBCs, producing oxygen or oxygen and carbon dioxide reduced red bloodcells.
 2. The method according to claim 1, wherein said gas circulationdevice is contained in a housing comprising a sorbent disposed betweensaid flushing gas source and said gas outlet manifold, and said methodfurther comprises removing oxygen or oxygen and carbon dioxide from saidflushing gas.
 3. The method according to claim 2, further comprisingdetermining levels of oxygen or carbon dioxide in said flushing gas,wherein said one or more gas sensor assemblies comprises a first gassensor assembly comprising a first partial pressure sensor disposedbetween said flushing gas source and said sorbent, and a second gassensor assembly comprising a second partial pressure sensor disposedbetween said sorbent and said gas outlet manifold.
 4. The methodaccording to claim 1, wherein said gas circulation device furthercomprises one or more load cells in communication with said controllerto regulate one or more flow regulator valves, and said method furthercomprises measuring the load of unprocessed RBCs, and controlling saidflowing.
 5. The method according to claim 4, wherein said controllerdetects a signal from said one or more load cells and then communicatesa signal to restrict or facilitate a flow of RBCs through said one ormore flow regulator valves.
 6. The method according to claim 1, whereinsaid one or more gas sensor assemblies comprises an oxygen sensor incommunication with said controller to regulate one or more flow valves,and said method further comprises measuring the level of oxygensaturation in said RBCs flowing through said OCDD device.
 7. The methodaccording to claim 6, wherein said controller detects a signal from saidoxygen sensor and then communicates a signal to restrict or facilitate aflow of RBCs through said one or more flow regulator valves.
 8. Themethod according to claim 1, wherein said flushing gas comprises Ar, He,N₂, Ar/CO₂, He/CO₂, N₂/CO₂, a combination of inert gasses, or anycombination of inert gasses and CO₂.
 9. The method according to claim 1,wherein said flushing gas source is selected from the group consistingof a pump, a vacuum, and a pressurized container.
 10. The methodaccording to claim 1, further comprising depositing said oxygen oroxygen and carbon dioxide reduced red blood cells in a blood storagebag.
 11. The method according to claim 1, further comprising adding anadditive solution to said RBCs prior to said flowing.
 12. The methodaccording to claim 11, wherein said additive solution is selected fromthe group consisting of OFAS3, SAGM, PAGG-SM, AS-1, AS-3, SOLX, MAPS,and PAGG-GM.
 13. The method according to claim 12, wherein said OFAS3has a pH ranging from about 5.5 to about 7.5.
 14. The method accordingto claim 13, wherein said OFAS3 has a pH of about 6.5.
 15. The methodaccording to claim 1, wherein said OCDD device further comprises aleukoreduction filter, and said method further comprises leukoreducingsaid RBCs.
 16. The method according to claim 1, wherein said OCDD devicefurther comprises a leukoreduction filter, and said method furthercomprises leukoreducing said oxygen or oxygen and carbon dioxide reducedred blood cells.
 17. The method according to claim 1, wherein said OCDDdevice further comprises a plasma separator, and said method furthercomprises separating plasma from said RBCs prior to said flowing. 18.The method according to claim 1, wherein said one or more gas sensorassemblies further comprise temperature, gas flow rate, total pressure,and humidity detectors.
 19. The method according to claim 1, whereinsaid oxygen or oxygen and carbon dioxide reduced red blood cells has ahemoglobin oxygen saturation level of less than 3%.
 20. The methodaccording to claim 1, wherein said oxygen or oxygen and carbon dioxidereduced red blood cells has a carbon dioxide partial pressure of lessthan 50 Torr at 37° C.